The damage type that Twitch deals is mostly Physical Damage.
Twitch's damage type breakdowns as follows:
Twitch's basic attacks infect the target, dealing 1/2/3/4/5 (+3% bonus Ability Power) (at levels 1/5/9/13/17) true damage each second over 6 seconds, stacking up to 6 times.
Twitch becomes Camouflaged and gains 10% Movement Speed for 10/11/12/13/14 seconds. This bonus triples when he is nearby an enemy champion that cannot see him. Twitch gains 40/45/50/55/60% Attack Speed for 5 seconds after exiting Ambush. Ambush resets when a champion dies while affected by Deadly Venom.Stealth - Camouflage: Twitch is hidden from view while enemy champions remain outside his detection radius. Attacking or casting spells ends Camouflage.
Twitch hurls a cask that adds a stack of Deadly Venom to all enemies struck and leaves behind a toxic cloud that persists for 3 seconds.Enemies that remain within the cloud have 30/35/40/45/50% (+6% bonus Ability Power) reduced Movement Speed and receive an additional stack of Deadly Venom each second.
Deals 20/30/40/50/60 physical damage plus an additional 15/20/25/30/35 (+30% bonus Ability Power) (+25% bonus Attack Damage) physical damage per stack of Deadly Venom to all nearby enemies affected by Deadly Venom. (Max Stack Damage: 200% bonus Attack Damage)
For 6 seconds Twitch gains 300 Attack Range and 40/55/70 Bonus Attack Damage.For the duration, his basic attacks become piercing bolts that deal 10% less damage to subsequent targets, down to a minimum of 60% damage.Stealth - Camouflage: Activating Spray and Pray does not end Camouflage.The extra distance that Twitch's bolts travel, scales with his bonus attack range
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